I got a set of DPS lotus 120s this year.
Positives of the weight savings. Carrying them in your arms. They are easy to pick up with your hands.
Negatives. They get deflected when crossing tracks. They don't have the mass to really power through anything. This is also a function of the soft flex in the tips.
Touring. The ski mostly slides on the snow, so you aren't really lifting it up every step. binding and boot weight makes a huge difference. ski weight, not so much. Also, skis tend to build up snow on the top sheets. A big fat ski tends to carry more snow, which reduces the weight savings.
Not that the skis are bad. They are a great ski. Just that the weight savings isn't really that important for skiing down. Except they are a joy to carry in your arms or on your back.
I don't ski park, I am sure that the reduced swing weight would be an asset there. Although it's not going to make you all of a sudden go from having trouble getting a 7 around, to stomping 10s. It's really the operator.